Latch opener mechanism for knitting machines



April 21, 1964 H. o. WERNER 3,129,572

LATCH OPENER MECHANISM FOR KNITTING MACHINES Filed Aug. 1, 1962 5 Sheets-Sheet l 6Q 42 (,5 e5 Q4 G! INVENTOR. HARRY O. WERNER A TTORNEY April 1964 H. o. WERNER 3,129,572

LATCH OPENER MECHANISM FOR KNITTING MACHINES Aug. 1, 1962 5 Sheets-Sheet 2 G3 32 G1 4 M;-

INVENTOR. H ARRY O. WERNER ATTORNEY Apri 1964 H. o. WERNER' LATCH OPENER MECHANISM FOR KNITTING MACHINES 5 Sheets-Sheet 5 Filed Aug. 1, 1962 INVENTOR. HARRY OWERNE i wffimaa A T TORNE Y April 21, 1964 H. o. WERNER 3,129,572

- LATCH OPENER MECHANISM FOR KNITTING MACHINES Filed Aug. l, 1962 5 Sheets-Sheet 4 F 157 HARRY flaw-ER A TTORNEY c4 kl 5 Sheets-Sheet 5 A TTORNE Y April 21, 1964 o, WERNER LATCH OPENER MECHANISM FOR KNITTING MACHINES I, ..Z.Z

United States Patent 3,129,572 LATCH GPENER MECHANISM FOR KNITTING MACHENES Harry 0. Werner, Philadelphia, Pa, assignor to Wiidman Jacquard Co., Norristown, Pa., a corporation of Pennsylvania Filed Aug. 1, 1962, Ser. No. 214,77 Claims. (Cl. 66-111) This invention pertains to a latch opener mechanism for knitting machines and, more particularly, to such a mechanism for a straight bar type knitting machine adapted to knit automatically jersey fabric in continuation of rib fabric.

It is a general object of the invention to provide a latch opener mechanism which will open and hold open all the latches of the latch needles simultaneously.

It is a further object of the invention to provide a latch opener mechanism that will operate automatically in timed relation with the latch needle bar when the latter is placed in position adjacent the spring beard needles for the purpose of knitting rib fabric.

It is a further object of the invention to control the latch opener hooks so that they hold the needle latches in the open position during the stitch measuring cycle to prevent unintended closing of the latches due to machine vibration, etc.

It is a still further object of the invention to provide latch opener hooks which are formed and disposed in such a manner that they also serve as a guard means to prevent stitch loops that are being pulled down off the noses of the sinkers into the hook portion of the latch needles from becoming displaced, such, for example, as getting in back and under the latches where they would be cast off the needles.

Further objects and advantages of the invention will become apparent from the following disclosure.

The producing of garment halves such as the fronts or backs of sweaters in fashioning type straight bar knitting machines, that is, such machines as that disclosed in US. patent application Serial No. 699,345, filed on November 27, 1957, wherein it is possible to knit true rib fabric, transfer automatically to the knitting of jersey fabric and continue jersey knitting for any desired extent, has been found to be more advantageous and desirous by providing this type of knitting machine with a latch opener mechanism. Since the above patent application is representative of the type of knitting machine to which the instant invention is applicable, reference may be had to that patent application for a detailed description of such a knitting machine.

This type of straight bar knitting machine utilizes two needle bars, a first needle bar preferably including spring beard needles and a second needle bar preferably including latch needles. The latch needle bar is cam controlled and to form rib fabric it is advanced to a position which places the latch needles in close proximity to the spring beard needles with which they are caused to function as disclosed in the above-mentioned application. After the completion of the rib section the latch needle bar by this cam means is automatically withdrawn to an inactive position and the spring beard needles continue to knit by themselves producing jersey fabric in continuation of said rib section.

According to the instant invention a latch opener mechanism is now provided for reasons set forth in the foregoing objects. The mechanism includes a latch hook bar which overlies the latch needle bar. It is provided with a plurality of inwardly directed latch hooks disposed along the length thereof and equivalent in number to the number of latch needles carried by the latch needle 3,129,572 Patented Apr. 21, 1964 bar. The mechanism is cam controlled and is caused to function in timed relationship with the cam means utilized to control the movement of the latch needle bar. When the latch needles are advanced to that position to knit and form rib in conjunction with the spring beard needles, and prior to the latch needles taking yarn, the latch hook bar is advanced to a position which places the tips of the latch hooks in contact with the upper hooked portion of the latch needles. The hook bar is then caused to move forwardly with respect to the knitting machine itself and at a slight incline to the horizontal causing the latch hooks to pull all of the needle latches open simultaneously. The latch hooks are then caused to dwell in a position which keeps them in contact with the open needle latches to prevent said latches from closing before the hooked portion of the needle has had an opportunity to take yarn. Additionally, the outer surface of the latch hooks serve as guards to prevent loops that are being pulled down off the sinker noses from becoming displaced such, for example, as getting in back of and under the latches where they would be cast off resulting in drop stitches and fabric of an inferior quality.

The invention will hereinafter be described in greater detail by reference to the accompanying figures of drawing, in which:

FIG. 1 is a section taken through a part of a fashioning type straight bar knitting machine to which the invention has been applied;

FIG. 2 is a sectional view through the knitting heads showing a needle latch being held open by a latch hook while measuring a stitch around a sinker and spring beard needle;

FIG. 3 is a view similar to that of FIG. 2 but showing the latch hook in dwelling position where it is caused to hold the needle latch open and act as a guard means to prevent displacement of a yarn loop being pulled off the nose of the sinker;

FIG. 4 is a view similar to that of FIG. 2 but showing the position the latch hooks are caused to assume prior to the opening of the latches and by means of the directional arrows, the direction is indicated which the latch needles and hooks must move to effect the opening of said latches;

FIG. 5 is a plan view of the linkage utilized to control the required movement of the latch needle bar and the latch hook bar;

FIG. 6 is a view in side elevation and on an enlarged scale showing the relationship between the latch hook and the needle prior to the opening of the needle latch;

FlG. 7 is an end view of the hook and needle shown in FIG. 6 illustrating one form of hook end that may be utilized to effect opening of the needle latches;

PEG. 8 is a view similar to that of FIG. 7 but showing a modified form of hook end which may be used;

FIG. 9 is a front elevational view of part of the knitting machine looking in the direction of the indicating arrow 9 in FIG. 1, showing the cams and linkages utilized to control movement of the latch needle bar and the latch hook bar;

FIG. 10 is a view similar to that of FIG. 4 but showing a portion of the fabric F, the direction it is caused to move as formed and the position of a yarn loop under the nose of a sinker;

FIG. 11 is a view similar to FIG. 1 but showing only the means for controlling the movement of the latch hook bar and for lifting the latch needle bar; and

FIG. 12 is a view similar to FIG. 1 but showing only the means for controlling the horizontal movement of the latch needle bar and catch bar.

Now referring to the figures of drawing, FIG. 1 illustrates that part of a knitting machine to which the instant invention has been applied and includes among other parts a main needle bar 21) which includes a plurality of spring beard needles 21 that assemble along the length thereof and extend upwardly therefrom. A plurality of knock-over bits 22 are carried in a known manner by a bar 23 and the usual sinkers 24 are utilized in a sinker head base 25.

A rib needle bed or latch needle bar 26 is located forward of and at right angles to the main needle bar 29. The various parts which comprise the mechanism of the instant invention derive their means of motion from the cams indicated generally by numeral 27 mounted on the knitting machines auxiliary cam shaft 23.

The latch needle bar 26 is slotted as at 29 in FIG. and forms a bed therein for slidable latch needles 31 which are adapted to operate at right angles and in conjunction with the spring beard needles 21 when forming rib fabric.

The latch needles are caused to move to and from their operating position simultaneously by means of a catch bar 32 which is provided with a slot 33 that is adapted to fit over the butts 34 of said latch needles (FIGS. 2 to 4). The latch needle bar 26 is provided with key members 35 and 35' on each end thereof, FIG. 9, which are adapted to fit into slots, one of which is shown at 36 in FIGS. 11 and 12, formed in the latch needle bar guides 37 and 37'. This needle bar is slidable horizontally in guides 37 and 37 by means of connecting links 38 and 38' the inner ends of which are pivotally attached to integrally formed lug members 39 and 39' which are centrally disposed with respect to the width of the needle bar and protrude downwardly from the underside of said needle bar and adjacent the ends thereof. The forward ends of the connecting links 38 and 38 are attached in a similar manner to the upper bifurcated end of upwardly directed arcuated bell crank lever arms 40 and 40. The hub portions 41 and 41' of these bell crank levers are rockable on a fixed horizontal shaft 42 and are provided with forwardly directed and substantially horizontal arcuated second arms 43 and 43 (FIGS. 9 and 12). These second arms are provided intermediate their ends with rollers or cam followers 44 and 44 which are adapted to bear against cams 45 and 45 by means of a spring 46 (left-hand only shown, FIG. 12) one end of which is attached to the end of said second arm and the opposite end at some suitable point on the lower portion of the knitting machine itself.

The majority of views in the drawings illustrate those parts utilized on the left-hand side of the machine; however, it is to be understood that similar parts of the opposite hand are utilized on the right-hand side as shown in FIG. 9 of the drawing which is a front elevational view showing many of the right-hand parts which correspond to the left-hand, and because of their similarity they are being given the same number as the left-hand parts but with the addition of a prime.

Rotation of cams 45 and 45' causes the cam followers 44- and 44' to follow the dictates of said cams thus rocking the bell crank lever arms 40 and ill back and forth sliding the needle bar in a like manner in timed relationship with the catch bar 32 and the latch opener mechanism, both of which will be more fully explained hereinafter.

The catch bar 32 which overlies the needles and which is adapted to control the movement of the latch needles 31 carried by the needle bar 26 is provided on each end thereof with a catch bar bracket 46 (left-hand only shown, FIGS. 1, 11 and 12) having a forwardly extending lug portion 47 which is adapted to receive pivotally one end of a catch bar connecting link 48. The right-hand side of the machine being of similar construction utilizes the same type of connecting link 48 and the forward ends of both are pivotally attached to the upper ends 49 and 49 of double armed levers generally indicated by numerals 50 and 50, respectively. The hub portions of these levers assemble on shaft 42 and are rockable thereon. They are provided with second arms 51 and 51. which extend in a 2?. generally downwardly direction and have attached to the lowermost ends thereof rollers or cam followers 52 and 52' which are caused to follow the outer periphery of rotating cams 53 and 53'. The dictates of these cams cause the upper arms 49 and 49 to move back and forth and being pivotally connected to the catch bar through the connecting links 48 and 48', said catch bar is caused to slide back and forth in timed relation with the knitting cycle to advance and remove the latch needles 31 to and from their operating position.

The latch needle bar is capable of being raised for the purpose of bringing the latch needles up under and through the sinkers to assist in equalizing the stitches in the same manner as the spring beard needles cast oif their stitches against the knock-over bits. This motion is accomplished by means of needle bar lifter links 54 and 54'. These links have their upper ends pivotally attached to the inner lower side of the latch needle bar guides 37 and 37 and their lower ends are attached in a like manner to rearwardly directed first arms of bell crank levers which are assembled and rockable on shaft 42. The drawing illustrates only the le t-hand bell crank lever (FIG. 11) and is generally indicated by numeral 55. The first arm of this lever is represented by numeral 56. FIG. 9 of the drawings show the second arms of both the left-hand and right-hand levers by dotted lines and they are indicated by numerals 57 and 57', respectively. The lower ends of these arms are provided with rollers or cam followers 58 and S8 and are caused to transmit the dictates of cams 59 and 59' to raise and lower the needle bar lifter links 54 and 54. The upper ends of these lifter links, being pivotally attached to the inner and lower portion of the latch needle bar guides 37 and 37', ermit the latter, which are pivotally attached to the machine as at 60, to pivot upwardly upon indication from the lifter links thus pushing the needle bar upwardly a sufficient distance to accomplish its intended function.

The mechanisms and motions thus far described form no part of the present invention and are further described in the above-mentioned application Serial No. 699,345.

Also, when transferring from rib to jersey knitting, or vice versa, the entire auxiliary shaft 28, together with the cams fixed thereupon, is caused to move to the left or to the right to position each of the rollers in contact with a different cam by a known type of shifting mechanism. In this manner the rib knitting mechanisms may be rendered inactive when knitting plain fabric.

The mechanism comprising the invention and which is caused to function in timed relationship with the aforementioned motions, includes a latch hook bar 61 positioned directly above the latch needle bar 26. The hook bar being of approximately the same length as the needle bar includes a plurality of latch opener hooks 62 equal in number to the number of latch needles carried by said needle bar. These hooks extend inwardly from the hook bar and are firmly positioned along the length thereof by means of a hook bar cap 63 which overlies the hook members and is firmly attached to the top inner surface of said hook bar.

FIGS. 6 and 7, being on an enlarged scale, clearly show the tip 62 of a latch opener hook 62 and the position it is caused to assume prior to its pulling the latch 31 of the needle 31 to the dotted line position depicted in FIG. 6.

The tips of the latch opener books 62 may be formed to any desired shape such as tip 62' in FIG. 7 which is generally concaved enabling the sides thereof to extend below the outer surface of the hook portion of the needle 31, thus permitting said sides to assume a position below the inner end of the latch 31'. A modified form of a latch opener hook tip 62" is shown in FIG. 8 and being of the chisel type, it is adapted to contact the outermost surface of the hook portion of the needle to effect opening of the latch 31' when making contact therewith.

The latch hook bar is provided on each end thereof with hook bar brackets indicated generally by numerals 64 and 64'. The body portion 65 of these brackets is substantially L-shaped with the lower inwardly directed portion serving as a base or seat for the latch hook bar 61, and the upwardly directed portion is provided with an adjustment screw 66 the tip of which is adapted to bear against said hook bar 61, thus permitting fine fore and aft adjustment of the latter. With respect to their assembled position on the knitting machine, the hook bar brackets 64 and 64' are provided with forwardly directed and integrally formed extensions which terminate in the form of hubs 67 and 67'. These hubs are pivotally attached by means of cap screws 68 and 68' to the upper ends of arcuated first arms 69 and 69' of bell crank levers indicated generally by numerals 70 and 70. The hub portions 71 and 71' of these bell crank levers are rockable on shaft 42 and their second arms 72 and 72 being substantially horizontal and forwardly directed are provided intermediate their ends with rollers or cam followers 73 and 73'. On the forward end of these bell crank levers second arms 72 and 72' there is attached one end of a coil spring 74 (left-hand only shown, FIG. 11) and the opposite end, being attached at a lower point on the machine, keeps the cam followers 73 and 73 in contact with the rotating cams 75 and 75' that are assembled on the machines auxiliary cam shaft 28. The dictates of cams 75 and 75' cause the arcuated first arms 69 and 69 of these bell crank levers to rock back and forth and the hook bar brackets 64 and 64', being pivotally attached to the upper ends thereof, cause the latch opener hooks and hook bar to move inwardly and outwardly in timed relationship with the aforementioned mechanisms to open the latches of the latch needles at the required time during the knitting cycle.

The underside of the latch hook bar 61 is provided with adjustment screws 76 on each end thereof. The head portions of these screws are caused to bear against the top of the catch bar 32 and serve as a means for controlling the height of the latch opener hooks.

In operation and in the producing of rib fabric, the horizontal bar of latch needles is caused to function in combination with the bar of vertical spring beard needles. When knitting jersey only, the spring beard needles are active and the latch needles are inactive. Prior to the knitting of rib the latch needle bar by the cam means heretofore described is caused to move inwardly toward its operating position. Before reaching this point, however, the hook portions of the latch needles are contacted by the tips 62 of the latch opener hooks which have also been moving inwardly in unison with the hook bar by the cam means herein described. After contact between the hooks of the latch needles and the tips of the latch opener hooks, movement of the two motions continues and the latch needles move to their operating position adjacent the spring beard needles, but due to the particular shape of the cam controlling the movement of the hook bar, this member is caused to reverse its direction of travel and as the latch opener hooks move along the hook portion of the latch needles, they contact the needle latches pulling them to the open position as shown in FIGS. 2 and 3 of the drawings. The latch opener hooks, being controlled by cam means, are adapted to hold the needle latches in the open position during the stitch measuring cycle to prevent possible closing of the latches due to machine vibration, etc. Additionally, these hooks, when holding the latches open, serve as a guard means to prevent the yarn loops from becoming displaced such as getting in back of and under latches where they would be cast off before completing the function of a stitch.

While one embodiment and a modification of the invention have been disclosed, it is to be understood that the inventive concept may be carried out in a number of ways. This invention is, therefore, not to be limited to the precise details described, but is intended to embrace all variations and modifications thereof falling within the spirit of the invention and the scope of the claims.

I claim:

1. A needle latch opener mechanism for flat knitting machines having a bar of latch needles adapted to knit rib fabric in combination with a bar of spring beard needles, a latch hook bar having in combination a plurality of latch opener hooks protruding from one side of said hook bar and equally spaced along the length thereof, a cam means for automatically moving said hook members into contact with said latch needles and for opening all the latches of said needles simultaneously.

2. In a fiat knitting machine having in combination two needle bars, the first bar having spring beard needles assembled therein and the second bar having latch needles attached thereto, a first cam means for moving all of said latch needles into a position for knitting rib fabric in combination with said spring beard needles and for withdrawing all of said latch needles at the completion of said rib permitting said spring beard needles to knit jersey fabric in continuation thereof, a latch hook bar having a plurality of latch opener hooks extending therefrom, a second cam means adapted to function in timed relation to said first cam means for placing said latch opener hooks into contact with the latches of said latch needles and for opening all of the same simultaneously.

3. In a flat knitting machine having in combination two needle bars, the first bar having spring beard needles assembled therein and the second bar having latch needles attached thereto, a first cam means for moving all of said latch needles into a position for knitting rib fabric in combination with said spring beard needles and for withdrawing all of said latch needles at the completion of said rib permitting said spring beard needles to knit jersey fabric in continuation thereof, a latch hook bar having a plurality of latch opener hooks extending therefrom, a second cam means adapted to function in timed relation to said first cam means for placing said latch opener hooks into contact with the latches of said latch needles and for opening all of the same simultaneously, said second cam means including a rotating cam, a cam follower and a cam follower linkage arm having one end thereof attached to said latch hook bar for moving said latch opener hooks toward and away from the latches of said latch needles.

4. A needle latch opener mechanism for flat knitting machines having a bar of latch needles adapted to knit rib fabric in combination with a bar of spring beard needles, a latch hook bar having in combination a plurality of latch opener hooks protruding from one side of said hook bar and equally spaced along the length thereof, a cam means for automatically moving said hook members into contact with said latch needles and for opening all the latches of said needles simultaneously, said hook bar and latch opener hooks being angularly disposed with respect to said bar of latch needles to facilitate the opening of said latches.

5. A needle latch opener mechanism for flat knitting machines having a bar of latch needles adapted to knit rib fabric in combination with a bar of spring beard needles, a latch hook bar having in combination a plurality of latch opener hooks protruding from one side of said hook bar and equally spaced along the length thereof, a cam means for automatically moving said hook members into contact with said latch needles and for opening all the latches of said needles simultaneously, said latch opener hooks being fixedly positioned in said latch hook bar.

References Cited in the file of this patent UNITED STATES PATENTS 110,479 Lee et al. Dec. 27, 1870 3,008,314 Knohl Nov. 14, 1961 FOREIGN PATENTS 84,802 Germany Jan. 21, 1896 25,046 Great Britain 1896 25,582 Great Britain 1899 

1. A NEEDLE LATCH OPENER MECHANISM FOR FLAT KNITTING MACHINES HAVING A BAR OF LATCH NEEDLES ADAPTED TO KNIT RIB FABRIC IN COMBINATION WITH A BAR OF SPRING BEARD NEEDLES, A LATCH HOOK BAR HAVING IN COMBINATION A PLURALITY OF LATCH OPENER HOOKS PROTRUDING FROM ONE SIDE OF SAID HOOK BAR AND EQUALLY SPACED ALONG THE LENGTH THEREOF, A CAM MEANS FOR AUTOMATICALLY MOVING SAID HOOK MEMBERS INTO CONTACT WITH SAID LATCH NEEDLES AND FOR OPENING ALL THE LATCHES OF SAID NEEDLES SIMULTANEOUSLY. 